Cecilia Sarto

Dioxin exposure, from infancy through puberty, produces endocrine disruption and affects human semen quality.

Background Environmental toxicants are allegedly involved in decreasing semen quality in recent decades; however, definitive proof is not yet available. In 1976 an accident exposed residents in Seveso, Italy, to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Objective The purpose of this study was to investigate reproductive hormones and sperm quality in exposed males. Methods We studied 135 males exposed to TCDD at three age groups, infancy/prepuberty (1–9 years), puberty (10–17 years), and adulthood (18–26 years), and 184 healthy male comparisons using 1976 serum TCDD levels and semen quality and reproductive hormones from samples collected 22 years later. Results Relative to comparisons, 71 men (mean age at exposure, 6.2 years; median serum TCDD, 210 ppt) at 22–31 years of age showed reductions in sperm concentration (53.6 vs. 72.5 million/mL; p = 0.025); percent progressive motility (33.2% vs. 40.8%; p < 0.001); total motile sperm count (44.2 vs. 77.5 × 106; p = 0.018); estradiol (76.2 vs. 95.9 pmol/L; p = 0.001); and an increase in follicle-stimulating hormone (FSH; 3.58 vs. 2.98 IU/L; p = 0.055). Forty-four men (mean age at exposure, 13.2 years; median serum TCDD, 164 ppt) at 32–39 years of age showed increased total sperm count (272 vs. 191.9 × 106; p = 0.042), total motile sperm count (105 vs. 64.9 ×106; p = 0.036), FSH (4.1 vs. 3.2 UI/L; p = 0.038), and reduced estradiol (74.4 vs. 92.9 pmol/L; p < 0.001). No effects were observed in 20 men, 40–47 years of age, who were exposed to TCDD (median, 123 ppt) as adults (mean age at exposure, 21.5 years). Conclusions Exposure to TCDD in infancy reduces sperm concentration and motility, and an opposite effect is seen with exposure during puberty. Exposure in either period leads to permanent reduction of estradiol and increased FSH. These effects are permanent and occur at TCDD concentrations < 68 ppt, which is within one order of magnitude of those in the industrialized world in the 1970s and 1980s and may be responsible at least in part for the reported decrease in sperm quality, especially in younger men.

Heat shock proteins in human cancer

The heat shock proteins (hsp) are ubiquitous molecules induced in cells exposed to sublethal heat shock, present in all living cells, and highly conserved during evolution. Their function is to protect cells from environmental stress damage by binding to partially denatured proteins, dissociating protein aggregates, to regulate the correct folding, and to cooperate in transporting newly synthesized polypeptides to the target organelles. The molecular chaperones are involved in numerous diseases, including cancer, revealing changes of expression. In this review, we mainly describe the relationship of hsp expression with human cancer, and discuss what is known about their post‐translational modifications according to malignancies.

Perinatal Exposure to Low Doses of Dioxin Can Permanently Impair Human Semen Quality

Background In recent decades, young men in some industrialized areas have reportedly experienced a decrease in semen quality. Objective We examined effects of perinatal dioxin exposure on sperm quality and reproductive hormones. Methods We investigated sperm quality and hormone concentrations in 39 sons (mean age, 22.5 years) born between 1977 and 1984 to mothers exposed to dioxin after the accident in Seveso, Italy (1976), and 58 comparisons (mean age, 24.6 years) born to mothers exposed only to background dioxin. Maternal dioxin levels at conception were extrapolated from the concentrations measured in 1976 serum samples. Results The 21 breast-fed sons whose exposed mothers had a median serum dioxin concentration as low as 19 ppt at conception had lower sperm concentration (36.3 vs. 86.3 million/mL; p = 0.002), total count (116.9 vs. 231.1; p = 0.02), progressive motility (35.8 vs. 44.2%; p = 0.03), and total motile count (38.7 vs. 98 million; p = 0.01) than did the 36 breast-fed comparisons. The 18 formula-fed exposed and the 22 formula-fed and 36 breast-fed comparisons (maternal dioxin background 10 ppt at conception) had no sperm-related differences. Follicle-stimulating hormone was higher in the breast-fed exposed group than in the breast-fed comparisons (4.1 vs. 2.63 IU/L; p = 0.03) or the formula-fed exposed (4.1 vs. 2.6 IU/L; p = 0.04), and inhibin B was lower (breast-fed exposed group, 70.2; breast-fed comparisons, 101.8 pg/mL, p = 0.01; formula-fed exposed, 99.9 pg/mL, p = 0.02). Conclusions In utero and lactational exposure of children to relatively low dioxin doses can permanently reduce sperm quality.

Modified expression of plasma glutathione peroxidase and manganese superoxide dismutase in human renal cell carcinoma.

Two‐dimensional polyacrylamide gel electrophoresis (2‐D PAGE) is a powerful tool to separate thousands of polypeptides and to highlight the modification of protein expression in malignant diseases. By applying 2‐D PAGE to ten normal human kidney and ten homologous renal cell carcinoma (RCC) tissues, we found two peptides in all ten normal tissues but not in RCCs and, conversely, two peptides were detected in all RCCs but not in normal tissues. Using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) and internal sequence analysis, the two first peptides were identified as two isoforms of plasma glutathione peroxidase (GPxP). The two other peptides isolated in all RCCs but not in normal tissues were identified by N‐terminal sequence analysis as multimeric forms of manganese superoxide dismutase (Mn‐SOD). No multimeric Mn‐SODs and only two monomeric forms were detected in normal tissues. GPxP and Mn‐SOD are metallo‐enzymes encoded on chromosome 5q32 and on chromosome 6p25, respectively. Their regions are within the locus 5q21 → qter and 6q21‐6q27 on which deletions and translocations are described in some cytogenetic studies of RCC transformation. Therefore, our results might suggest a correlation between the modified expression of GPxP and Mn‐SOD in tumor tissues and chromosomal modifications, and that the two proteins may be putative markers for diagnosis of RCC.*

Proteomic analysis in clear cell renal cell carcinoma: identification of differentially expressed protein by 2-D DIGE

Renal cell carcinoma (RCC), the most common neoplasm affecting the adult kidney, is characterised by heterogeneity of histological subtypes, drug resistance, and absence of molecular markers. Two-dimensional difference gel electrophoresis (2-D DIGE) technology in combination with mass spectrometry (MS) was applied to detect differentially expressed proteins in 20 pairs of RCC tissues and matched adjacent normal kidney cortex (ANK), in order to search for RCC markers. After gel analysis by DeCyder 6.5 and EDA software, differentially expressed protein spots were excised from Deep Purple stained preparative 2DE gel. A total of 100 proteins were identified by MS out of 2500 spots, 23 and 77 of these were, respectively, over- and down-expressed in RCC. The Principal Component Analysis applied to gels and protein spots exactly separated the two sample classes in two groups: RCC and ANK. Moreover, some spots, including ANXA2, PPIA, FABP7 and LEG1, resulted highly differential. The DIGE data were also confirmed by immunoblotting analysis for these proteins. In conclusion, we suggest that applying 2-D DIGE to RCC may provide the basis for a better molecular characterization and for the discovery of candidate biomarkers.

Renal cell carcinoma: handling and treatment.

The quality of samples and of pre‐analytical steps are crucial in all biological tests, this is dramatically true in proteomics analysis. In renal cell carcinoma preparation for two‐dimensional gel electrophoresis the time elapsed between sample collection and treatment, and the heterogeneity of tissues are considered in order to obtain high quality and reproducibility of spots. The mechanical dissection and cell separation by magnetic beads coated with anti‐Ber and EP4 antibodies to minimize the contamination of nonepithelial cells are described.

Differential expression of AQP1 in microdomain-enriched membranes of Renal Cell Carcinoma

Human aquaporin‐1 (AQP1) is the most studied member of the aquaporin family, acting as molecular water channel. It is also considered a differentiation marker for proximal renal tubular cells, from which clear cells renal cell carcinoma (RCC) originates, playing an important role in urine formation. We therefore studied AQP1 expression at the proteomic level in RCC and normal tissues, mainly focusing on microdomain‐enriched membranes in which AQP1 is highly concentrated. Subcellular fractions were prepared through differential centrifugation, and microdomain‐enriched fractions were purified from a plasma membrane‐enriched fraction by 1% Triton X‐100 treatment followed by ultracentrifugation in sucrose gradient. After SDS‐PAGE and Western blot analyses with antibodies against AQP1, lower expression levels of AQP1 isoforms were observed in each subcellular fraction of RCC compared to fractions from normal kidney tissues. The presence of AQP1 in the immunoreactive bands was verified by MALDI‐TOF‐MS and LC‐ESI‐MS/MS analysis. Glycosylation of AQP1 was also investigated using N‐glycosidase F, confirming the presence of a N‐glycosylated isoform of AQP1 in the 35–45‐kDa region. These results highlight an under‐expression of AQP1 protein and its glycosylated isoforms in homogenate and subcellular fraction obtained from RCC tissue compared to adjacent normal cortex.

Insight on Renal Cell Carcinoma Proteome

Several efforts are today focused on studying the most wide form of tumor affecting human kidney, renal cell carcinoma (RCC), because of our inability to diagnose and treat this very aggressive neoplasia. Different complementary approaches based on genomic and proteomic tools are used to highlight its altered molecular processes, and new developed methods and techniques are implemented in the search of possible biomarkers. However, notwithstanding the great work done by several groups and the enormous amount of information present in literature, knowledge about its pathogenesis is still incomplete, and several markers of RCC are proposed but not yet validated.

IgMκ-IgMλ pair quantitation in the clinical laboratory practice

BACKGROUND New Hevylite® assay quantifies the immunoglobulin classes, including IgM bound to light chains, allowing distinguishing immunoglobulins involved and uninvolved in plasma cell disorders. OBJECTIVE To compare data obtained by IgM Hevylite® (IgM-HLC) assay with conventional methods used in routine laboratory practice for monitoring IgM plasma cell disorders. METHODS Serum samples (n=122) from 50 patients with IgM monoclonal protein (MP) identified by Immunofixation (IFE) before the beginning of the study were collected during monitoring from December 2012 to September 2014 (2 Waldestroms macroglobulinemia, 4 NH-lymphoma, 44 MGUS) and were assessed using IgM Hevylite® (HLC) assay, Capillary Electrophoresis (CE), Immunofixation (IFE), serum Free Light Chain (FLC) assay and total IgM measurements. RESULTS IgM MP was detected by IFE in 85/122 samples (71 IgMk, 10 IgMl, 4 IgMk/IgMl), while in 37/122 was undetectable although CE measured small MP, probably as a consequence of disease stimulating inflammatory immuno-response. Among the 85 positive samples, the HLC ratio but not the FLC ratio was altered in 36 samples while in 4 sera only FLC was altered. Out of 37 IFE negative samples 24 had normal HLC and FLC ratios. CONCLUSIONS Since the partial overlap of abnormalities identified by HLC and FLC assays, IgM Hevylite assay can provide valuable information on the evolution of IgM monoclonal disease and may support the recognition of a transitory monoclonality leading to an improvement in routine laboratory practice.

Genus-level identification of dermatophytes by MALDI-TOF MS after 2 days of colony growth

Matrix‐assisted laser desorption‐ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) is becoming a popular technology in clinical microbiology. It is a fast and highly specific method for the routine identification of micro‐organisms. In this study, we evaluated the suitability of dermatophyte identification after only 2 days of colony growth using MALDI‐TOF MS. Two protein extraction protocols were also evaluated consisting of either formic acid alone or of ethanol‐formic acid‐acetonitrile to achieve a complete protein extraction. Morphology‐based techniques were used as the diagnostic standard methods and MALDI‐TOF MS results were obtained using the manufacturers spectral library. Using the formic acid protein extraction protocol after 2 days of colony growth, 70 and 46% of dermatophytes were properly identified at the genus and species‐level respectively. The addition of ethanol‐formic acid‐acetonitrile extraction protocol increased the identification to 90 and 62%. Based on our observations, we propose a two‐step workflow for the fast and reliable identification of dermatophytes after only 2 days of colony growth. This flow chart consists of a first direct deposition procedure with the addition of formic acid, followed by a complete protein extraction when dermatophyte identification is not successful.